A polyphenylene ether resin is a useful high polymeric material because of its heat resistance, mechanical strength, and electrical characteristics. However, a polyphenylene ether resin is often found unsatisfactory in molding properties, solvent resistance, and impact resistance. In an attempt to compensate for these disadvantages, it has been proposed to blend a polyphenylene ether resin with other resins, such as polyester, polyamide, polyolefin, etc., but blending of these resins brings about unfavorable results, such as layer separation and reduction of mechanical strength due to poor compatibility between these resins and the polyphenylene ether resin.
It is well known to blend a styrene/butadiene block copolymer or a styrene/isoprene block copolymer or a hydrogenation product thereof in order to improve impact strength of a polyphenylene ether resin as described, e.g., in Japanese Laid-Open Patent Application No. 79151/81 and U.S. Pat. No. 4,309,514. This technique, however, still fails to compensate for the poor solvent resistance of the polyphenylene ether resin. It has also been proposed to blend a polyphenylene ether resin with the above-described block copolymer and a polar polymer, e.g., polyamide and polyester, but the resulting composition is still unsatisfactory due to poor compatibility between the block copolymer and the polar polymer.